EFFECT OF HOT-WATER TREATMENT IN THE MORTALITY OF FRUIT FLY EGGS

This work was carried out to verify hot water treatment efficiency on the mortality of Ceratitis capitata eggs. The following combinations of temperatures and immersion times were applied using a bi-factorial design: temperatures of 25°C (control ), 42, 44, 46, 48 and 50°C, and immersion times of 0, 20, 30, 40, 50, 60 and 90 min. Eight replicates were evaluated for each treatment, each one containing 20 eggs, with a maximum age of 24 hours, separated by electron microscope, placed in porcelain crucibles (capacity of 50 ml) containing 10 ml of distilled water. After the treatment, the eggs were removed, transferred to petri dish plates and stored in B.O.D. at 25°C. After 24 hours of the process, the plates were evaluated for the mortality of eggs. According to the results, we concluded that C. capitata eggs were tolerant to hot water up to 44°C for 20 min. Therefore, the use of temperatures equal to or above 46°C for 20 min or more promoted 100% of mortality. The mortality of C. capitata eggs increased with the increase of the temperature and exposition time.